1. Technical Field
The present disclosure relates to, in a communication system in which a device and a home gateway are connected, a cryptographic communication device and a cryptographic communication method for controlling a connection between devices using cryptography.
2. Description of the Related Art
In recent years, it has been expected to provide service such that a household electrical appliance or a AV device in a home is connected to a network and service is provided using various kinds of history information collected therefrom to a cloud server. In this service, a home gateway is installed in a home and transmission of history information from a household electrical appliance to a cloud server is performed through the home gateway. By securely setting the connection between the home gateway and the household electrical appliance, communication within a home is controlled so as to prevent information from being leaked via a wireless communication and prevent an unauthorized connection to a network in a home from being made by spoofing or the like.
Wi-Fi Alliance has established a standard called Wi-Fi Protected Setup that allows it to easily make a connection between devices (Wi-Fi Alliance, “Wi-Fi CERTIFIED Wi-Fi Protected Setup: Easing the User Experience for Home and Small Office Wi-Fi Networks (2010)”, [online] December, 2010 [Searched Apr. 18, 2014], Internet <URL:http://www.wi-fi.org/ja/file/wi-fi-certified-wi-fi-protected-setup % E2%84% A2-easing-the-user-experience-for-home-and-small-office-wi>). As described above, it is possible to realize the secure connection between the home gateway and the household electrical appliance.
In a conventional Wi-Fi wireless connection, a plurality of devices may be connected to an access point. Japanese Patent No. 4606055 discloses a method of selecting a cryptography method with a highest security level from cryptography methods employable in common by devices located on a network.